The Allen-Bradley 1794-IB8 is a Flex 1794 Digital DC Input module. It is fitted inside the terminal bus making a connection with the field devices and the I/O bus. Modules can be inserted or removed under power since the I/O module does not have any direct wiring. It in turn saves time and removes system restarting inefficiency. It is very popular because of its reliability, flexibility, cost-effectiveness, and modularity. The 1794-IB8 module has 8 current sinking inputs with 24V DC nominal On-State voltage, 10 – 31.2V DC On-State voltage range, and 1.5mA minimum Off-State current. It has a maximum power dissipation of 3.5W at 31.2V DC. Terminal base units compatible with it are the 1794-TB3 and the 1794-TB3S. It is installed using a DIN rail. It has various communication options such as ControlNet, DeviceNet, EtherNet/IP, and Universal Remote I/O. The 1794-IB8 module has 16 yellow LEDs as status indicators for each channel. LEDs indicate corresponding input devices and output signals. It also has D and XT versions of standard modules for diagnostics and extreme environments, reducing panel and maintenance costs. It has a 0 - 55 °C (32 - 131 °F) operating temperature and a 5 - 95% noncondensing relative humidity.